Diethyl cyanomethyl phosphonate as an antimicrobial agent

ABSTRACT

Diethyl cyanomethyl phosphonate can be used to inhibit and/or prevent the growth of undesirable algae, bacteria, fungi, yeast, and other microorganisms. This invention is particularly concerned with the bacteriostatic and bactericidal properties of diethyl cyanomethyl phosphonate compounds against species of Proteus, Salmonella, Shigella, Staphylococcus and Xanthomonas.

United States Patent Kerst et al.

[ DIETHYL CYANOMETHYL PHOSPHONATE AS AN ANTIMICROBIAL AGENT [75] Inventors: Al F. Kerst; John D. Douros, Jr.,

both of Littleton, Colo.

[73] Assignee: The Gates Rubber Company,

Denver, C010.

[22] Filed: Oct. 28, 1970 [21] App]. No.: 84,905

[52] U.S. Cl 424/210, 71/67, 7l/86 Oct. 9, 1973 Primary ExaminerAlbert T. Meyers Assistant Examiner-Leonard Schenkman Attorney-Raymond Fink, H. W, Oberg, Jr. and Curtis H. Castleman, Jr.

[5 7 ABSTRACT Diethyl cyanomethyl phosphonate can be used to inhibit and/0r prevent the growth of undesirable algae, bacteria, fungi, yeast, and other microorganisms. This invention is particularly concerned with the bacteriostatic and bactericidal properties of diethyl cyanomethyl phosphonate compounds against species of Proteus, Salmonella, Shigella, Staphylococcus and Xanthomonas 52 Claims, No Drawings DIETHYL CYANOMETHYL PHOSPHONATE AS AN ANTIMICROBIAL AGENT BACKGROUND OF THE INVENTION While there is no dearth of organophosphorous microbial growth inhibitors existing today, the antimicrobial properties of diethyl cyanomethyl phosphonate have not been previously discovered. Furthermore, few of the commercially available organophosphorous growth inhibitors offer diethyl cyanomethyl phosphonates activity against such a broad spectrum of algae, bacteria, fungi, yeast, et cetera. This broadactivity is often desirable since the inhibition of one microorganism species or group of species may create an imbalance which often results in the rampant growth of other deleterious microorganisms.

SUMMARY OF THE INVENTION According to the present invention, it has been found that diethyl cyanomethyl phosphonate PCH-;CN ll C2HO O is a very effective antimicrobial agent. The compound diethyl cyanomethyl phosphonate is well known and may be prepared according to the methods disclosed in German Pat. No. 1,108,208 to W. Stily et al. The diethyl cyanomethyl phosphonate used to establish the present invention was prepared by reacting triethyl phosphite with chloromethylacetonitrile using the Arbusov method. In the preferred method of preparation, substantially equimolecular proportions of chloroacetonitrile and triethyl phosphite are reacted in a round bottom flask equipped with a dry ice condenser. The mixture is heated to 115 to 130 C whereupon ethylchloride evolves. The reaction is carried out for about 4 hours and the final reaction mixture is vacuum distilled to give a 75-80 percent yield of diethyl cyanomethyl phosphonate which can be identified by its boiling point (121- 122 C at 0.2 mm Hg), infrared spectrum and proton nuclear magnetic resonance spectrum.

DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLE 1 Antibacterial and Antiyeast Activity The in vitro effectiveness of diethyl cyanomethyl phosphonate against bacteria and yeast species is established in the following manner. One loopful of each of the investigated bacteria or yeast is transferred from agar slants to ml. of trypticase soy broth and incubated at 37 for 18 hours. At the end of this period, the bacteria or yeast is seeded into the same medium (1.5-2 percent agar) in which the original inoculum was prepared. The bacteria is then seeded at 1 ml. of inoculum per 250 ml. of medium, which is equivalent to at least 1 X 10 cells/ml as determined by dilution platecount or nephelometer readings. The resultant mixtures are poured into heat-resistant sterile petri dishes at a temperature of 45 C. Analytical filter paper discs 1.2 cm. in diameter are used for the agar diffusion technique. Each disc is saturated with 0.08 ml. of the solubilized diethyl cyanomethyl phosphonate compound ug./disc) and placed on the surface of the hardened agar. The plates are then incubated at 37 C. for 18 hours. The activity of the diethyl cyanomethyl phosphonate compounds is established by measuring the zone of inhibition in centimeters. Untreated control plates are used as a basis for comparison and these exhibit a profuse growth of bacteria. The results of these tests are as follows:

Gram positive and Gram negative bacteria Streptococcus hemolytic Group A Streptococcus hemolytic Group B Zone of Inhibition in Centimeters Xanthomona: phaseoli ATCC No. 9563 Staphylococcus aureus ATCC No. 2091 Escherichia coli ATCC No. 9637 Sht'gella boydii ATCC No. 9212 Sht'gella boydt'i ATCC No. 9905 Sht'gella sonnet' MMV 6654 Shigella flexneri TYPE 6 MMV 760 Shigella flexneri TYPE 4 MMV 6625 Shigella dysentert'ae TYPE 2 MMV 6673 Nelsseria gonnrrhaeae ATCC No.' 19424 Net'ssert'a intracellularis Netlrseria meningitide: ATCC No. 13077 Listeria monocytogenes ATCC No. 15813 Vibrio fetus ATCC No. 19296 Vibrt'a chalerae ATCC No. 14035 Proteus vulgaris ATCC No. 4984 Erwinia carotovora ATCC No. 495

Mycobactert'um bulyricum ATCC No. 11314 Mycabactert'um fartut'tum, Debos ATCC No. 4243 Mycobacterium avium ATCC No. 19421 Mycobacterium bovis ATCC No. 19274 Mycobacterium phlei ATCC No..-11782, phage host xlebstelln pneumomae 2?] Micrococcus letragena 2.9 ATCC No. 10875 Micrococcus melitertsis ATCC No. 19399 Micrococcus lyrodeikticus ATCC No. 4698 Corynebactertum diphtheriae 2.2 ATCC No. 19409 Corynebactcriurn haemolyticum ATCC No. 9345 Diplococcus lntracellularis Diplococcus pneumoniac ATCC No. 6303 Hemopht'lus hemolyticur ATCC No. 10014 Hemaphilus influenzae ATCC No. 19418 Hemophilia: paminfluenzae ATCC No. 7901 Hemopht'lur sut's ATCC No. 19417 Hemophilus vaginalis ATCC. No. 14018 Bacterm'des nigrescens Bacteroides pneumosintcs Baclemt'des serpens Brucella abortus ATCC No. 4315' Brucclla melitensis ATCC No. 19396 Brucella suis ATCC No. 4312 Compound: Diethyl cyanomethyl phosphonate Concentration (ugldisc) MICROORGANISM 90.9 30.0 9.0 Salmonella sp. 3.1 2.4 1.9 ATCC No. 9120 Salmonella typhimurtum miraglia 3.6 2.2 1.3 SR4 1 Salmonella No. 45 3.1 2.1 1.4 MMU 1063 Salmonella B/d 3.0- 2.2 1.4 MMU 6674 Salmonella 3.2 2.3 1.7 MMU 6668 Shigella boydii 1.2 0.8 0.6 ATCC No. 9212 Shigella boydii 1.1 0.8 0 ATCC N0. 9905 Shigella flexrteri Type 6 1.0 0.7 0 MMU 760 Shigella flexneri Type 4 1.1 0.9 0.3 MMU 6625 Shigella dyrenteriae Type 2 1.2 0.7 0.5 MMU 6673 Shigella sonnet 1.0 0.7 0 MMU 6654 Pseudomonas aeruginosa 1.1 0 O ATCC No. 10145 Pseudamonas aerugr'nosa 1.1 0 0 ATCC No. 8709 Pseudomonas aeruginosa 1.4 0.9 0 ATCC No. 12055 Pseudomonas aeruginosa 1.2 0.7 0 23 v Pscudomonar malmphilt'a 1.1 0.7 8.6

G 107 Pseudomonas K997 1.0 0.7 0 Pseudomonas K966 1.0 0.5 0

- Proteus vulgaris 2.4 2.7 0

ATCC N0. 9484 Proteus vulgan': 2.9 1.9 0

M Ny

ATCC No. 8427 Proteus vulgaris 2.4 1.6 0 ATCC N0. 4699 Proteus vulgart's 2.3 1.7 0 ATCC No. 6896 Proteus vulgarir 2.7 1.9 0 ATCC No. 9920 Proteus vulgaris 2.5 1.6 0 ATCC No. 6897 Proteus vulgarls 2.6 1.6 0 ATCC No. 12454 Proteus. mirabt'ltlr 2. 6 TR 0 ATCC No. 9961 Proteus morganii G951 2.6 TR 0 Proteus mt'rabilis G912 2.4 TR 0 Proteus mirabilis K723 2.6 1.8 0

Streptococcus faecalt's Comments: h hazy zone tr trace This data indicates that diethyl cyanomethyl phosphonate compounds can be used to inhibit many important types of diseases. For example, they can be used against:

Disease Produced Major cause of bovine mastitis Bacterial endocarditis Cause of scours and secondary cause of bovine mastitis Major cause of fish disease (trout,

pike) Numerous animal and plant infections are caused by various pseudomonads. Urinary infections are notable examples.

Various species of Erwinia attack commercial crops of carrots, tobacco, potatoes, squash. et cetera.

Various species of Xanthomonas cause a variety of diseases in plants such as sugar cane, rice, sugar beets, cotton, walnuts, wheat, rye, barley, beans, et

Bacteria Staphylococcus aureus Escherichia coli Proteus vulgarir Pseudomonas aerugt'nosa E m'inia cartovora Xan thomanas phascolt' I cetera.

The demonstrated antibacterial activity of diethyl cyanomethyl phosphonate compounds against Staphylococcus aureus and Escherichia coli is of particular interst to the field of pharmacology since the disclosed activity indicates that these compounds can be formulated as powders, salves, and ointments for administration in the treatment of burns and bacterially induced inflammations such as abscesses, dermatitis, rashes and the like, particularly in domestic animals.

Although the precise mode of action whereby diethyl cyanomethyl phosphonate inhibits bacteria growth is not completely understood, it is believed that the diethyl cyanomethyl phosphonate compounds of this invention may serve as chemical antagonists; that is, as chemicals which compete with enzymes essential to the development of many bacteria. Since enzymes perform their catalytic function by virtue of their affinity for their natural substrate; any compound resembling a substrate in its chemically critical aspect may also have an affinity for the enzymes. If this affinity is great enough, the analog will displace the normal substrate from the enzyme and will prevent the growth reaction from taking place. it is believed that diethyl cyanomethyl phosphonate has a chemical affinity for an es- .sential site on one enzyme necessary for bacterial cally acceptable carrier such as oils, salves and ointments, together with adjuvants comprising surface active agents, detergents, dispersing agents, stabilizers and other modifiers which may facilitate the handling and application of the antibacterial material. In the case of the in vitro applications of the compositions of this invention, it is difficult to predict with precision what in all cases will constitute a therapeutic dose even on a weight basis. Variable factors such as type, duration and severity of infection and mode of administration may be determining factors for the establishment of therapeutic doses.

Those skilled in the art will recognize that the above data indicates that the scope of this invention should not be limited to any particular disease species or to any particular type of animal or plant life. For example, the noted activity of diethyl cyanomethyl phosphonate against Xanthomonas phaseali suggests that this compound will also prove to be of value against such other Xanthomonas species as Xanthomonas transluscens, Xanthomonasjuglandis, Xanthomonas vesica toria, Xdnthomonas barbareae, Xanthomonas pelargonii, Xanthomonas alfalfae, Xanthomonas vasculorum, et cetera. Xanthomonas species are known to cause diseases of tomatoes, sugar cane, rice, sugar beets, cotton, walnuts, wheat, rye, barley, and beans. Some of the more noteworthy Xanthomonas related diseases are X anthomonas vesicatoria (Bacterial Leaf Spot of Tomatoes), Xanthomonas phaseoli (Common Bacterial Blight of Bean), Xanthomonas vasculorum (Gumming Disease of Sugar Cane) and Xanlhomonas malvacearum (Bacterial Blight of Cotton).

EXAMPLE Ill Antifungal Activity The antifungal activity of diethyl cyanomethyl phosphonate compounds is established by treating Fusarium oxysporum, Fusarium roseum, Rhizopus nigricans, Rhizopus stolonij'er, Aspergillus niger and Alternaria solani test fungi in the following manner: One loopful of each of the tested viable fungi cultures, spores and mycelia is transferred from an agar slant to an 80 ml. portion of the nutrient broth composed of oatmeal agar, Czapeks, Sabouraud and deoinized water to volume. The 80 ml. portion of the fungi and broth is ten placed in a sterile shake flask (300 ml.) and the flask is placed on a rotary shaker for 96 to 120 hours at room temperature. At the end of this incubation time period, ml. of the liquid are homogenized and placed in another sterile shake flask (300 ml.) containing 80 ml. of the above nutrient broth and 60 ppm of diethyl cyanomethyl phosphonate. The flasks are placed on a rotary shaker operating at 240 rpm at room temperature for 3 to 9 days. After this second incubation time, the flasks are taken off and examined for visible fungal growth and mycelial weights are determined. Untreated controls are used as the basis of comparison and these display profuse fungal growths containing species of Fusarium, Rhizopus, Aspergillus and Alternaria. The results of these tests indicate that the diethyl cyanomethyl phosphonate compounds of this invention impart a substantial degree of inhibition of fungal growth at 60 ppm.

EXAMPLE 1V Antifungal and Antiyeast Activity To further define the antifungal activity of diethyl cyanomethyl phosphonate the seeded agar plates are prepared by transferring the cultures from slants washed with saline or phosphate buffers to the surface of hardened Sabouraud-Dextrose agar plates. Again, as in the case of Example I, the diethyl cyanomethyl phosphonate is tested by impregnating filter paper discs 1.27 cm. in diameter) with 0.08 ml. of the solubilized diethyl cyanomethyl phosphonate compounds ug/disc) and placing them on the surface of the hardened agar. The plates are then incubated at 30 C. for 18 hours. The activity of diethyl cyanomethyl phosphonate is established by measuring the zone of inhibition in centimeters. Untreated control plates are used as as basis for comparison and these exhibit a profuse growth of bacteria. The results of these tests are as follows:

Zone of Inhibition in Centimeters 1.7

Microorganism Aspergillus niger ATCC No. 1004 EXAMPLE V Secondary Fungal Screen A secondary screen using the techniques of Example IV produces the following results at the diethyl cyanomethyl phosphonate concentrations indicated:

Concentration (ug/disc) MICROORGANISM 30.0

Rhodotorula sp. 2.0 0 Duke Rhiznpus .rrolomj'er 2.0 Tr ATCC No. 10404 Monascus purpurea 2.0 0 0U Fusarium roseum 1.9 0 UFCC 1166 F usarium oxysporum cubense 3.0 1.6 URCC 1122 Scopulariopsis sp. 3.0 1.8 OU

Aspergillus niger 1.7 0 SR1 Aspergillus niger 2.7 O Aspergillus .rydowi 2.3 0 ATCC No. 1017 Aspergillus nidulans 3.0 0 ATCC No. 10074 Aspergillus flavus 1.9 0 ATCC No. 9643 Aspergillus amslelodami 2.8 0 ATCC No. 1001 Aspergillus fumigatus 1.9 0

Cephalosporium acremanium 3.1 Tr ATCC NO. 10141 Ccphalosporium sp. 2.1 0 OU Phoma pigmznrovora 3.6 1.6 ATCC No. 12569 Paecilomycex varioli 4.6 2.0 ATCC No. 1114 Nigrospora sphaerica 6.0 3.5 ATCC No. 11687 Absidia spinosa 3.2 1.8 ATCC No. 6648 Mucor racemasus 3.6 1.8 ATCC No. 1216 Thamnldium elegans 2.6 1.7

NSC 8997 ATCC No. 9984 Penicillin"! rubrum 3.6 2.6 ATCC No. 10520 Penicilliarn nomlum 2.8 O

Beauvaria bassiana 5.0 2.8 MV 1341 Beam/aria lenella 2.3 1.9 MV 1919 Phialophora verrucosa 6.2 4.0 U

Cl'adosporium lrichoides 4.6 2.0 OU

Torula bergeri 1.7 0 CU Monosporum apiospermum 3.5 0 CU Alternaria .mlani 2.3 O ATCC No. 639

Geotrichum sp. 2.6 0 0U Verricillium alb0atrum 2.5 O ATCC No. 10833 Trichophyron mentagrophytes 3.7 2.2 ATCC No. 9129 Trichophyian menlagropliyres 4.8 3.1 ATCC No. 8215 Trichophylon ronsurans 7.4 4.4 ATCC No. 10217 Cercaspora belicola 4.6 1.8 ATCC No. 12825 Pyrhium arrhenomaner 2.1 1.9 ATCC No. 12531 Helminlhosporium aryzae 3.8 1.2

ATCC No. 11000 Comments: ng no growth Tr Trace EXAMPLE V1 Secondary Candida Screen Concentration (rig/disc) MICROORGANISM 92.0 30.0 Candida albicans 1.7 0 DD Candida albicans 1.8 1.7h ATCC NQ. 752

Candida albicans 1.7 O .ATCC No. 1165] Candida al'bicans 1.6 0 Duke 2548 Candida albicans 1.6 0 0U Candida albicans 1.7 0

Mt. Vernon SR1 220 Candida albicans 1.7 0 Mt. Vernon SR1 221 Candida sp. 1.7 0 Mt. Vernon 788 Candida sp. 1.6 0 Mt. Vernon 512 Candida sp. 1.7 0 Mt. Vernon 976 Candida sp. 1.7 0 Mt. Vernon 950 Candida krusei Tr O 0U Candida guill'iermandii 1.8 0 OU Candida tropic-alt: 1.7 0 Duke 284'] Candida psuedorropicalis 1.7 0 Duke 2543, U. Columbia Candida intermedia 2.5 Tr Duke 2605, CBS

Candida zeyianoide: 2.6 Tr

Duke 2609 Candida pulcher-rima 2.2 Tr Duke 2603 Comments: .h hazy zone considered on the basis of its demonstrated performance in such primaryevaluations and then progressively judged in subsequent studies. A wide range of pathogens, representative of economically important diseases, can be used to help define diethyl cyanomethyl phosphonates biological activity and to assure high degrees of success under field conditions. The following disease organisms, crops and reference standards may be used in such evaluations:

Disease Disease Organism Reference Compound Powdery Mildew of Cucumbers Erysiphe cichoracearum Maneb, Karathane Leaf Rust of Wheat Puccinia rubigo-vera Maneb, Karathane Leaf Rust of Wheat Puccinia rubigo-vem Plantvax Rice Blast Disease Piri'cularia oryzae Blasticidin Downy Mildew of Sugar Beet Peronospom schaclii Karathane Downy Mildew of Lima Bean Phytophthora phaseoli Karathane Bean Rust Uromyces phaseoli var. Iypica Maneb Powdery Mildew of Wheat Erysiphe graminis Karathane Powdery Mildew of Apple Pndosphaem leucatricha Karathane Powdery Mildew of Roses Sphaerolheca pannosa var. Karathane rasae Powdery Mildew of v Cantalope Erysiphe cicharacearum Karathane Leaf Spot of Wheat Helminrhosporium sau'vum Maneb Early Blight of Tomato Allernaria solani Maneb Rice Blast Disease Piricularia oryzae Blasticidin Cerocspora Leaf Spot of Sugar Beets Cercospora beticnla Maneb Septoria Leaf Spot of Celery Seproria apii-gmveolennlr Maneb Apple Scab Venluria inaequalis Cyprex Common Bacterial Blight of Bean Xanlhomonas phaseali Streptomycin Sulfate Wherever possible, the applicants recommend the use of in vivo"'procedures to test the diethyl cyanomethyl phosphonate compositions of this invention to demonstrate their efficacy under more realistic conditions. However, not all pathogens lend themselves to such techniques. In order to provide additional spectrum definitions, the following fruit'rotting, storage decay and bacterial pathogens may be tested by in vitro methods:

Brown Rot of Stone Fruits Sclerotinia frucricola Captan Grey Mold of Fruit and Vegetables Batryis cinerea Maneb Rhizopus Fruit and Vegetable Rot Rhizopus nigricans Maneb- Citrus Green Mold Penicillium digiratum Maneb Citrus Blue Mold Penicilliam italicum Karathane Bacterial Disease of Many Fruit Crops Pseudomonas syringae Captan Bacterial Soft Rot Erwim'a caratarora Captan In their plant protection aspects, the diethyl cyanomethyl phosphonate compounds of this invention may be used in the manner known to the organophosphorus crop protection art; that is, they can be made up in solid or liquid formulations. Examples of solid formulations are dust, wettable powders, granules and pellets. As a dust, diethyl cyanomethyl phosphonate compounds may be dispersed in powdered solid carriers such as talc, soaps, soapstone, attapulgus clay as well as other finely divided solids known to the dusting art. When formulated as wettable powders, the active component may be employed in conjunction with inert fillers which may be of the clay type carrier or nonclay type, in conjunction with various combinations of wetting agents and emulsifiers which permit the adaptation of the concentration as a free-flowing powder for dispersion in the field.

Each of these carriers may in turn contain other carriers or extenders which are ordinarily non-reacting or inert substances such as sand,clays, talc, sawdust, alkaline earth carbonates, oxides, phosphates and the like as well as diatomaceous earth, micas or other suitable materials. When liquid formulations are desired, liquid extenders, dilutants or carriers of a non-reactive nature may be utilized. Examples of such materials are alcohols, ketones, glycols, aromatic hydrocarbons, petroleum fractions such as octane and various other distillates. From these considerations, it will also be recognized that the above formulations with slight modifications may be used in the field of animal husbandry as dusting powders and salves.

Where it is desired to use the aforementioned wettable powders or liquid formulations, either emulsified, dispersed or suspended in water or other fluids, one or more of the class of materials herein referred to as adjuvants can also be incorporated into the powder, dust or liquid formulation. These adjuvants comprise surface active agents, detergents, wettable agents, stabilizers, dispersing agents, suspending agents, emulsifying agents, spreaders, stickers and conditioning agents generally. To their modifying characteristics these adjuvants may facilitate handling and application and infrequently enhance or potentiate the diethyl cyanomethyl phosphonate compositions of this invention in their biological activities by mechanisms which are frequently not well understood. A satisfactory but not exhaustive list of these adjuvants appears in Soap Chemical Specialties, Volume 31, No. 7, Page 61; No. 8, Pages 38-61; No. 9, Pages 52-67; and No. 10, Pages 38-67 (1955). See also, Bulletin No. 607 of the Bureau of Entomology and Plant Quarantine of the United States Department of Agriculture.

'An additional advantage of diethyl cyanomethyl phosphonate is its compatibility with a variety of other bactericidal and fungicidal materials. For example, it may be convenient to combine diethyl cyanomethyl phosphonate with one or more other adjuvants, carriers, pesticides, biocides or fungicides of various structures. For example, diethyl cyanomethyl phosphonate fungicidal inhibitors may be combined with insecticidal materials such as chlordane, benzene hexachlorides, DDT, DDD, the insecticidal carbamates, polychlorinated terpenes, parathions, methozychlor, insecticidal phosphates, phosphorothioates, phosphorodithioates and with fungicides such as sulphur, quinones,

10 dodecylgaunidine and metal dimethyldithiocarbamates.

There are many other considerations which may make some methods of application more favored than others. These considerations may include the type of organisms on which the compound is to be administered, the degree of activity, the degree of activity toward the particular organism, and side effects. Also to be considered is the cost of production and the characteristic solubility of diethyl cyanomethyl phosphonate in the carrier material.

The broad spectrum of antifungal activity afforded by diethyl cyanomethyl phosphonate can also be utilized in the formulation of disinfectant solutions, paints, coatings, films and polymeric materials in order to protect against disease and rot caused by various fungi species. When used as a disinfectant, suitable formulations may be prepared by mixing the compound with an emulsifying agent in the presence of organic solvents and then diluting it with water to form an aqueous emulsion containing the diethyl cyanomethyl phosphonate. Suitable emulsifying agents include, e.g., alkylbenzenesulfonates, polyalkene glycols, et cetera. Aqueous emulsions of diethyl cyanomethyl phosphonate are particularly suited for use in disinfectant solutions used in washing hospital floors and walls. The following examples further illustrate the antifungal properties of diethyl cyanomethyl phosphonate.

EXAMPLE VII Preparation of a Vinyl Coating Resistant to Mildew Deterioration A vinyl coating is prepared using a commercially available preparation without the fungal growth inhibitor.

An identical vinyl coating is prepared except that 2 percent by weight of diethyl cyanomethyl phosphonate is incorporated into the coating formulation.

Two sets of components such as asbestos tubing, silkwrapped transformers and rayon-wrapped solenoids are obtained. One set is sprayed with the vinyl coating containing inhibitor, the other with the identical coating without inhibitor.

EXAMPLE VIII Preparation of Plastici zers Resistant to Mildew A commercial thermoplastic monomer is divided into portions which are treated as follows.

Portion 1: To the first portion is added 2 percent by weight of diethyl cyanomethyl phosphonate and 10 percent by weight of dimentylnaphthalate as plasticizer. The monomer is polymerized and molded into 3-inch diameter discs, one-quarter inch in thickness prior to testing.

Portion 2: To this portion is added 2 percent by weight of diethyl cyanomethyl phosphonate and 10 percent by weight of butyl isodecylphthalate as plasticizer. The monomer is polymerized and molded as above.

Portion 3: This portion is the untreated control of Portion 1 containing no fungal inhibitor but 10 percent by weight of dimethylphthalate as plasticizer. Again, the polymerization and molding are identical.

Portion 4: This portion is the untreated control of Portion 2 containing no fungal inhibitor but 10 percent by weight of butyl isodecylphthalate as plasticizer. The polymerization and molded are described above.

EXAMPLE IX Vinyl Coatings and Plasticizers For Fungal Resistance 'The vinyl coated articles and controls for Examples VII and VIII are placed in an air-tight high temperature and high humidity chamber maintained at 80 F. and 95% humidity to stimulate tropical temperature and humidity conditions. After a months exposure the vinyl coated articles treated with inhibitor are only slightly attacked by rot while the articles coated with vinyl without the diethyl cyanomethyl phosphonate inhibitor are well rotted. The two untreated control polymer discs are examined and found to be blackened and mildew rotted. Isolates of Aspergillus, Fusarium and known species of yeasts are prepared from the deteriorated discs. The discs containing the diethyl cyanomethyl phosphonate fungal inhibitor are not adversely affected.

EXAMPLE X Algaecidal Properties of Diethyl Cyanomethyl Phosphonate kistrodesmus, Anabaena, Synura, Oscillatoria, Cocco chloris, Chlamydomonas and Lyngbya are each maintained in Chu No. Broth Medium (Calcium nitrate,

0.040 grams; Potassium phosphate, 0.010 grams; Magnesium sulphate, 0.025 grams; Sodium carbonate 0.020 grams; Sodium silicate, 0.025 grams; Ferric citrate, 0.003 grams; Citric acid, 0.003 grams; and deionized water; 1.000 ml.) in the presence of sunlight. Hardened Chu No. 10 agar plates are inoculated with cotton swabs saturated with the respective algae broth cultures. The diethyl cyanomethyl phosphonate is tested by impregnating filter paper discs (1.27 cm. in diameter, No. 740-E, Schleicher and Schuell, Keene, N. H.) with a solution of the diethyl cyanomethyl phosphonate at the concentrations indicated. The saturated filter discs are placed on the surface of the seeded agar plates and the optimum growth temperature of 25 to 27 C. is maintained. Untreated control plates are used as a basis for comparison and these exhibited a profuse growth of algae. The results of these tests are expressed as inhibition zone diameters.

Inhibi- Inhibi- Inhibi- Inhibition tion tion tion Zone (cm) Zone (cm) Zone (cm) Zone Algae for 92 for 30 for 9 for 3 ug/disc ug/disc ug/disc ug/disc Scenedcsmur basilensis 5.5 3.5 2.7 1.7 Taft EEC 83 Scenedermu: obliquus 5.5 4.0 3.0 2.0h Taft EEC 92 Scenedesmus obliquus 5.0 3.2 1.8h 0 SR] EEC 3I5 Chlarella vulgaris total 4.5 3.7 O ATCC No. 9765 Chlarella ellipsoidea 4.0h 2.6h l .8h 0 Taft EEC-95 Chlorella pyrenaidosa 3.7 2.5 0 O TaftEEC-l2l Chlorella pyrenaidosa 4.7 3.5 2.5 v 1.7 ATCC 11469 Pleclonema nolalum 5.5 4.7 3.5 O Taft EEC I72 Anacystis nidulans 5.0 4.0 3.l 0 Taft EEC l34 Ankistrodesmus var. acicularis 4.7H 4.0 2.7h 0 Taft EEC 28 Anabaena catenula 5.2 3.4 2.l Tr SRI EEC 3I5 Synura ulvella 5.5 3.2 1.8 0 UI Osillatoria corneli 6.2 3.0 3.4 0

Coccochloris elebans 6.7 5.7 4.5 0 SR! Chlamydomonas radian 5.0 3.3 0 0 UA Lyngbya sp. 4.7 3.7 2.3 0 Taft EEC l66 h hazy zone Comments:

. tr trace As was the case with the bacteria, it should be recognized that the scope of this invention should not be limited to any particular species. For instance, the algaecidal activity of diethyl cyanomethyl phosphonate against Chlorella vulgaris, Chlorella ellipsoidea and Chlorella pyrenoidosa suggests that the compound will also prove to be of value against other species such as Chlorella va'riegata, et cetera. Similar possibilities exist for species of the other genera whose activity was shown to be arrested by diethyl cyanomethyl phosphonate. It should be recognized also that other appropriate algae genera may well afford additional opportunities to futher define the degree and spectrum of the algaecidal activity disclosed in this invention. Since no firm procedure can be laid down for the sequencing of such evaluations or for a selection among the more than 20,000 known algae species the diethyl cyanomethyl phosphonate compounds of this invention must be considered on the basis of their demonstrated performance in these primary evaluations and then progressively judged in subsequent studies. These evaluations should include but not be limited to the following algae genera.

TASTE AND ODOR CAUSING ALGAE GENERA Asterionella Peridinium Nitella Anabaena Mallomonas Dinobryon Microcystis Aphanizomenon Volvox Uroglenopsis Staurastrum Pandorina Hydrodictyon Ceratium Synura Synedra Coelosphaerium CLEAN WATER ALGAE GENERA Rhizoelonium Merismopedia Meridion Pinnularia Aphanothece Chromulina Cladophora Ulothrix Phacotus Rhodomonas Navicula Staurastrum Surirella Chamaesiphon Lemanea Cyclotella Micrasterias Cocconeis Chrysococcus Calothrix Microcoleus Ankistrodesmus FILTER CLOGGING ALGAE GENERA Anabaena Closterium Spirogyra Chroococcus Tabellaria Tra'chelornonas Dinobryon Rivularia Asterionella Cymbella Melosira Palmella Chlorella Cyclotella Diatoma Synedra Navicula F ragilarai Tribonema Oscillatoria POLLUTED WATER ALGAE GENERA Arthrospira Tetraerlron Anabaena Merismopedia Euglena Phacus Fhormidium Spirogyra Gloeogapsa Carteria Chlorococcum Stigeoclonium Lepocinclis Oscillatoria Gomphonema Nitzschia Lyngbya Chlamydomonas Chlamydobotrys SURFACE WATER ALGAE GENERA Actinastrum Euastrum Zygncma Nodularia Gonium Staurunels C oelastrum Desmidium Sphaerocystis Euglena Pediastrum Scenedesmus Micractinium Eudorina Oocystis Mougeotia Gomphosphaeria RESERVOIR ALGAE GENERA Chara Audouinella Compsopogon Phormidium Tetraspora Bathrachospermum Ulothrix Achnanthes Cymbclla Cladephora Stigeoclonium Bulbochaete Gomphonema Lyngbya Draparnaldia The scope of this invention should encompass the use of this compound in waters of all types such as lakes, rivers, ponds, streams, reservoirs, swimming pools and oceans as well as recirculating industrial waters. These compounds can be used to prevent the initial occurrence of algae or they can be used on bodies of water with algae already blooming. The diethyl cyanomethyl phosphonate compounds of the present invention are also advantageous in that they are degradable with none of the degradation products being toxic to fish and most fish food organisms at algae killing concentrations.

Another important advantage of diethyl cyanomethyl phosphonate compounds in their algaecidal applications is that they can be made up in solid or liquid formulations. Examples of solid formulations are dust, wettable powders, granules and pellets. Solid formulations, particularly floating solid formulations, may be preferred in combating algae which grow on surface waters. As a dust, diethyl cyanomethyl phosphonate compounds may be dispersed in powdered solid carriers such as talc, soap, soapstone, attapulgus clay, as well as other finely divided solids. When formulated as Wettable powders, the active diethyl cyanomethyl phosphonate component may be employed in conjunction with inert fillers which may be of the clay type carrier or non-clay type in conjunction with various combinations of wetting agents and emulsifiers which permit adaptation as a free flowing powder. Each of these carriers may in turn be combined with other carriers which are ordinarily non-reacting or inert substances such as sand, clays, talc, sawdust, alkaline earth carbonates, oxides, phosphates and the like, as well as diatomaceous earth, micas or other suitable materials.

When liquid formulations aredesirable, liquid extenders or carriers of a non-reactive nature may be utilized. These compositions should contain approximately 01 to 20 percent by weight and preferably 0.1 to 3 percent and most preferably-0.5 to 2 percent of the active diethyl cyanomethyl phosphonate ingredient. Solvents which may be used in the preparation of such compositions would include alcohols, ketones, glycols, mineral spirits and aromatic solvents such as benzene, xylene, nitrobenzene, dimethylformide. Furthermore, to assist in the rapid and complete dispersion in water systems, these compositions may also contain approximately 5 to 30 percent by weight and preferably to l5 percent by weight of surface-active agents. Suitable surfaceactive agents include sodium dialkyl sulphates, sodium alkylbenzene sulfonates, sodium carboxylates and the non-ionic surfactants such as ethoxylated fatty acid alcohols and amines.

Diethyl cyanomethyl phosphonate is compatible with a wide variety of other algaecidal, bactericidal and fungicidal materials. For example, it may be convenient to combine diethyl cyanomethyl phosphonate compositions with one or more of the other bactericides, fungicides or algaecides. For example, common fungicides and bactericides such as sulphur, inorganic salts such as copper sulphate, activated colloidal silver compounds, copper naphthenate and zinc acetate, as well as substituted hydrocarbons and quaraernary ammonium compounds, may be employed.

Other considerations may make some method of application and use of diethyl cyanomethyl phosphonate more favored than others. These considerations may include the type of organisms on which the compound is to be administered, the degree of activity, the degree of inhibition toward the algae organism and possible side effects. Also to be considered is the cost of production and the characteristic solubility of diethyl cyanomethyl phosphonate in the carrier compounds.

In their algaecidal aspects the applicants have discovered that diethyl cyanomethyl phosphonate compounds are active algaecides at relatively low concentrations. For example, it has been discovered that these compounds have imparted algaecidal activity at concentrations as low as 0.1 ppm. The amount of diethyl cyanomethyl phosphonate added to the water will, of course, vary depending upon-such factors as the type of algae present, the nature of the body of water, i.e., flowing stream versus small lake, et cetera, and the inherent ability of the body of water to support algae growth. This inherent ability in turn depends upon such factors as exposure to sunlight, pH, nutrient capabilities, and the like. In mostcases, however, the concentration of diethyl cyanomethyl phosphonate required to kill or inhibit growth of algaes will vary from 0.1 to 10 ppm, the preferred amount is in the range of 0.8 to 5 ppm. These compounds can be added to the water according to conventional techniques for algaecide applications. When treating a lake or body of water which is relatively calm, the conventional procedure is to spray an aqueous solution of the algaecide over the surface of the water. The diethyl cyanomethyl phosphonate generally will be predissolved in the types of solvents previously mentioned. In the case of moving water, such as in a water treatment plant or industrialfacility, the algaecide can be added to the water in small amounts at periodic intervals. For economic reasons, volume usages such as in lakes, streams, reservoirs, as distinguished from specialized uses such as in aquatic gardens, and industrial applications, the concentrations of the diethyl cyanomethyl phosphonate algaecides probably will not be more than 0.8 to 5 ppm of the water containing the algae.

Having thus disclosed our invention, we claim:

1. A method of killing or inhibiting the growth of microorganisms selected from the group consisting of fungi, Gram positive bacteria and Gram negative bacteria which comprises contacting said microorganisms with diethyl cyanomethyl phosphonate in an amount effective to kill or inhibit the growth of said microorganisms.

2. The method of claim 1 wherein the Gram positive bacteria are selected from the group consisting of Staphylococci, Corynebacter, Listeria, Micrococci, Myobacterium, Diplococci, Streptococci and Xanthomonas.

3. The method of claim 2 wherein the Staphylococci is Staphylococcus aureus.

4. The method of claim 2 wherein the Corynebacter are selected from the group consisting of Corynebacterium diphtheriae and Carynebacterium haemolyticum.

5. The method of claim 2 wherein the Listeria is Listeria monocytogenes.

6. The method of claim 2 wherein the Micrococci are selected from the group consisting of Micrococcus tetragena, Micrococcus melitensis and Micrococcus lysodeiktt'cus.

7. The method of claim 2 wherein the Mycobacterium are selected from the group consisting of M ycobacterium avlum, Mycobacterium bovt's, Mycobacterium phlei, Mycobacterium fortuitum and Mycobacterium bu tyricum.

8. The method of claim 2 wherein the Diplococci are selected from the group consisting of Diplococcus intracellularis and Diplacoccus pneumoniae.

9. The method of claim 2 wherein the Streptococci are selected from the group consisting of Streptococcus hemolytic, group A, and Streptococcus hemolytic, group B.

10. The method of claim 2 wherein the Xanthomonas is X anthomonas phaseoli.

11. The method of claim 1 wherein the Gram negative bacteria are selected from the group consisting of Escherichia, Shigella, Salmonella, Vibrio, Neisseria, Hemophilus, Bacteriodes, Brucella, Proteus, Pseudomonas and Erwinia.

12. The method of claim 11 wherein the Escherichia is Escherichia coli. 7

13. The method of claim 11 wherein the Shigella are selected from the group consisting of Shigella dysenteriae, Shigella' 'sonnei, Shigella flexneri and Shigella boydii. t

14. The method of claim 11 wherein the Salmonella are selected from the group consisting of Salmonella derby, Salmonella enteritis, Salmonella gallinarium, Salmonella panama, Salmonella paratypht', Salmonella pullorum and Salmonella typhosa.

15. The method of claim 11 wherein the Vibrio are selected from the group consisting of Vibrio cholerae and Vibrio fetus.

16. The method of claim 1 1 wherein the Neisseria are selected from the group consisting of Neisseria gonorrhoeae, Neisseria intracellularis and Neisseria meningitides.

17. The method of claim- 1 l wherein the Hemophilus are selected from the group consisting of Hemophilus selected from the group consisting of Proteus vulgaris,

Proteus morganni and Proteus mirabilis.

21. The method of claim 1 1 wherein the Pseudomonas are selected from the group consisting of Pseudomonas aeruginosa, Pseudomonas maltopht'lia, Pseudomonas K997 and Pseudomonas K955.

22. The method of claim 11 wherein the Erwinia is Erwinia carotovora.

23. The method of claim 1 wherein the microoganism are present on animals or plants and are contacted with an effective amount of diethyl cyanomethyl phosphonate together with an acceptable carrier.

24. The method of claim 1 wherein the fungi are selected from the group consisting of Fusarium, Penicillium, Aspergillus, Altemaria, Rhizopus, Candida, Rhodotorula, Monascus, Scopulariopsis, Cephalosporium, Phoma, Paecilomyces, Nigrospora, Absidia, Thamnidium, Phycomyces, Beauvaria, Phialophora, Cladosporium, Torula, Monosporum, Geotrichum, Verticillium, Trichophyton, cercospora, Pythium, Helminthosporium and Microsporum.

'25. The method of claim 24 wherein the Fusarium is selected from the group consisting of Fusarium roseum, F usarium oxysporum and F usarium oxysporum cubense.

26. The method of claim 24 wherein the Penicillium is selected from the group consisting of Penicillium rubrum and Penicillium notatum.

27. The method of claim 24 wherein the Aspergillus is selected from the group consisting of Aspergillus niger, Aspergillus sydowi, Aspergillus nidulans, Aspergillus flavus, Aspergillus amstelodami, and Aspergillusfumigatus.

28. The method of claim 24 wherein the Alternaria is Alternaria solani.

29. The method of claim 24 wherein the Rhizopus is Rhizopus stolonifer.

30. The method of claim 24 wherein the Candida is selected from the group consisting of Candida albicans, Candida krusei, Candida quilliermondii, Candida tropicalis, Candida pseudotropt'calis, Candida pulcher-rima, Candida intermedia and Candida zeylanoides.

31. The method of claim 24 wherein the Rhodotorula is Rhodotorula sp. Duke.

32. The method of claim 24 wherein the Monascus is Monascus purpurea.

33. The method of claim 24 wherein the Scopulariopsis is Scapulariopsis sp. OU.

34. The method of claim 24 wherein the Cephalosporium is selected from the group consisting of Cephalosporium acremonium and Cephalosporium sp. 0U.

35. The method of claim 24 wherein the Phoma is Phoma pigmentovora.

36. The method of claim 24 wherein the Paecilomyces is Paecilomyces varioti.

37. The method of claim 24 wherein the Nigrospora is Nigrospora sphaerica. I

38. The method of claim 24 wherein the Absidia is Absidia spinosa.

39. The method of claim 24 wherein the Mucor'is' Mucor racemosus.

40. The method, of claim 24 wherein the Thamnidium is Thamnidium elegans.

41. The method of claim 24 wherein the Phycomyces is Phycomyces nitens.

42. The method of claim 24 wherein the Beauvaria is selected from the group consisting of Beauvaria bassiana and Beauvart'a tenella.

43. The method of claim 24 wherein the Phialophora is Phialophora verrucosa. I

44. The method of claim 24 wherein the Cladosporium is Cladosporium trichoides.

45. The method of claim 24 wherein the Torula is Torula bergeri. v

46. The method of claim 24 wherein the Monosporum is Monosporum apiospermum.

18 50. The method of claim 24 wherein the Pythium is Pythium arrhenomanes.

51. The method of claim 24 wherein the Helminthosporium is Helminthosporium oryzae.

'52. The method of claim 24 wherein the Microsporum is Microsporum gypseum. 

2. The method of claim 1 wherein the Gram positive bacteria are selected from the group consisting of Staphylococci, Corynebacter, Listeria, Micrococci, Myobacterium, Diplococci, Streptococci and Xanthomonas.
 3. The method of claim 2 wherein the Staphylococci is Staphylococcus aureus.
 4. The method of claim 2 wherein the Corynebacter are selected from the group consisting of Corynebacterium diphtheriae and Corynebacterium haemolyticum.
 5. The method of claim 2 wherein the Listeria is Listeria monocytogenes.
 6. The method of claim 2 wherein the Micrococci are selected from the group consisting of Micrococcus tetragena, Micrococcus melitensis and Micrococcus lysodeikticus.
 7. The method of claim 2 wherein the Mycobacterium are selected from the group consisting of Mycobacterium avium, Mycobacterium bovis, Mycobacterium phlei, Mycobacterium fortuitum and Mycobacterium butyricum.
 8. The method of claim 2 wherein the Diplococci are selected from the group consisting of Diplococcus intracellularis and Diplococcus pneumoniae.
 9. The method of claim 2 wherein the Streptococci are selected from the group consisting of Streptococcus hemolytic, group A, and Streptococcus hemolytic, group B.
 10. The method of claim 2 wherein the Xanthomonas is Xanthomonas phaseoli.
 11. The method of claim 1 wherein the Gram negative bacteria are selected from the group consisting of Escherichia, ShigelLa, Salmonella, Vibrio, Neisseria, Hemophilus, Bacteriodes, Brucella, Proteus, Pseudomonas and Erwinia.
 12. The method of claim 11 wherein the Escherichia is Escherichia coli.
 13. The method of claim 11 wherein the Shigella are selected from the group consisting of Shigella dysenteriae, Shigella sonnei, Shigella flexneri and Shigella boydii.
 14. The method of claim 11 wherein the Salmonella are selected from the group consisting of Salmonella derby, Salmonella enteritis, Salmonella gallinarium, Salmonella panama, Salmonella paratyphi, Salmonella pullorum and Salmonella typhosa.
 15. The method of claim 11 wherein the Vibrio are selected from the group consisting of Vibrio cholerae and Vibrio fetus.
 16. The method of claim 11 wherein the Neisseria are selected from the group consisting of Neisseria gonorrhoeae, Neisseria intracellularis and Neisseria meningitides.
 17. The method of claim 11 wherein the Hemophilus are selected from the group consisting of Hemophilus hemolyticus, Hemophilus influenzae, Hemophilus parainfluenzae, Hemophilus suis and Hemophilus vaginalis.
 18. The method of claim 11 wherein the Bacteriodes are selected from the group consisting of Bacteroides nigrescens, Bacteroides pneumosintes and Bacteroides serpens.
 19. The method of claim 11 wherein the Brucella are selected from the group consisting of Brucella abortus, Brucella melitensis and Brucella suis.
 20. The method of claim 11 wherein the Proteus are selected from the group consisting of Proteus vulgaris, Proteus morganni and Proteus mirabilis.
 21. The method of claim 11 wherein the Pseudomonas are selected from the group consisting of Pseudomonas aeruginosa, Pseudomonas maltophilia, Pseudomonas K997 and Pseudomonas K955.
 22. The method of claim 11 wherein the Erwinia is Erwinia carotovora.
 23. The method of claim 1 wherein the microoganism are present on animals or plants and are contacted with an effective amount of diethyl cyanomethyl phosphonate together with an acceptable carrier.
 24. The method of claim 1 wherein the fungi are selected from the group consisting of Fusarium, Penicillium, Aspergillus, Alternaria, Rhizopus, Candida, Rhodotorula, Monascus, Scopulariopsis, Cephalosporium, Phoma, Paecilomyces, Nigrospora, Absidia, Thamnidium, Phycomyces, Beauvaria, Phialophora, Cladosporium, Torula, Monosporum, Geotrichum, Verticillium, Trichophyton, Cercospore, Pythium, Helminthosporium and Microsporum.
 25. The method of claim 24 wherein the Fusarium is selected from the group consisting of Fusarium roseum, Fusarium oxysporum and Fusarium oxysporum cubense.
 26. The method of claim 24 wherein the Penicillium is selected from the group consisting of Penicillium rubrum and Penicillium notatum.
 27. The method of claim 24 wherein the Aspergillus is selected from the group consisting of Aspergillus niger, Aspergillus sydowi, Aspergillus nidulans, Aspergillus flavus, Aspergillus amstelodami, and Aspergillus fumigatus.
 28. The method of claim 24 wherein the Alternaria is Alternaria solani.
 29. The method of claim 24 wherein the Rhizopus is Rhizopus stolonifer.
 30. The method of claim 24 wherein the Candida is selected from the group consisting of Candida albicans, Candida krusei, Candida quilliermondii, Candida tropicalis, Candida pseudotropicalis, Candida pulcher-rima, Candida intermedia and Candida zeylanoides.
 31. The method of claim 24 wherein the Rhodotorula is Rhodotorula sp. Duke.
 32. The method of claim 24 wherein the Monascus is Monascus purpurea.
 33. The method of claim 24 wherein the Scopulariopsis is Scopulariopsis sp. OU.
 34. The method of claim 24 wherein the Cephalosporium is selected from the group consisting of Cephalosporium acremonium and Cephalosporium sp. OU.
 35. The method of claim 24 wherein the Phoma is Phoma pigmentovora.
 36. The method of claim 24 wherein the Paecilomyces is Paecilomyces varioti.
 37. The method of claim 24 wherein the Nigrospora is Nigrospora sphaerica.
 38. The method of claim 24 wherein the Absidia is Absidia spinosa.
 39. The method of claim 24 wherein the Mucor is Mucor racemosus.
 40. The method of claim 24 wherein the Thamnidium is Thamnidium elegans.
 41. The method of claim 24 wherein the Phycomyces is Phycomyces nitens.
 42. The method of claim 24 wherein the Beauvaria is selected from the group consisting of Beauvaria bassiana and Beauvaria tenella.
 43. The method of claim 24 wherein the Phialophora is Phialophora verrucosa.
 44. The method of claim 24 wherein the Cladosporium is Cladosporium trichoides.
 45. The method of claim 24 wherein the Torula is Torula bergeri.
 46. The method of claim 24 wherein the Monosporum is Monosporum apiospermum.
 47. The method of claim 24 wherein the Verticillium is Verticillium albo-atrum.
 48. The method of claim 24 wherein the Trichophyton are selected from the group consisting of Trichophyton mentagrophytes and Trichophyton tonsurans.
 49. The method of claim 24 wherein the Cercospora is Cercospora beticola.
 50. The method of claim 24 wherein the Pythium is Pythium arrhenomanes.
 51. The method of claim 24 wherein the Helminthosporium is Helminthosporium oryzae.
 52. The method of claim 24 wherein the Microsporum is Microsporum gypseum. 